When a testicle rotates and twists the cord that brings blood to the pouch of skin containing the testicles, called the scrotum.

Testicular torsion is a medical emergency. It's most common between ages 12 and 18. But it can occur at any age, even before birth. Most often, no clear event causes testicular torsion.

Testicular torsion symptoms can include sudden pain, swelling or a change in color of the scrotum. A person also may have upset stomach, frequent urination or fever.

Testicular torsion treatment involves surgery. If treated quickly, the testicle usually can be saved. But when blood flow has been cut off for too long, the testicle becomes badly damaged and may need to be removed.